Download 8.3 Photosynthesis assessment statements

Potential command term assessment statements
AHL Topic 8: Metabolism, cell respiration and photosynthesis
8.3 Photosynthesis
Essential Idea: Light energy is converted into chemical energy.
Nature of science: Developments in scientific research follow improvements in apparatus—sources of
14C and autoradiography enabled Calvin to elucidate the pathways of carbon fixation.
Explain how the light-dependent reactions take place in the intermembrane space of the thylakoids.
 State that reduced NADP and ATP are produced in the light-dependent reactions.
 Explain the absorption of light by photosystems to generate excited electrons.
 Explain the photolysis of water to generate electrons for use in the light-dependent reactions.
 Outline the transfer of excited electrons occurs between carriers in thylakoid membranes.
 Explain how excited electrons from Photosystem II are used to contribute to generate a proton
gradient.
 Explain how ATP synthase in thylakoids generates ATP using the proton gradient.
 State that excited electrons from Photosystem I are used to reduce NADP.
Explain how the light-independent reactions also known as the Calvin Cycle take place in the stroma.
 State that in the light-independent reactions a carboxylase catalyses the carboxylation of ribulose
bisphosphate.
 Explain how Glycerate 3-phosphate is reduced to triose phosphate using reduced NADP and ATP.
 Outline how triose phosphate is used to regenerate RuBP and produce carbohydrates.
 State that ribulose bisphosphate is reformed using ATP.
Outline Calvin’s experiment to elucidate the carboxylation of RuBP
Explain how the structure of the chloroplast is adapted to its function in photosynthesis.
Annotate a diagram to indicate the adaptations of a chloroplast to its function including:
 the large surface area of thylakoids for light absorption
 the small space inside thylakoids for accumulation of protons
 the fluid stroma of the chloroplasts containing the optimal conditions and enzymes of the Calvin cycle
Discuss the Global Artificial Photosynthesis (GAP) project aims to create an artificial “leaf” within the next
decade. An electronic version of the leaf that creates oxygen and hydrogen from water and sunlight has
already been invented and will be developed for use in the next decade.
Describe the experimental and investigative skills used in the elucidation of photosynthesis including Hill´s
method demonstrating electron transfer in chloroplasts by observing DCPIP reduction, immobilization of a
culture of an alga such as Scenedesmus in alginate beads and measurement of the rate of photosynthesis by
monitoring their effect on hydrogencarbonate indicator.
Theory of Knowledge: The lollipop experiment used to work out the biochemical details of the Calvin
cycle shows considerable creativity. To what extent is the creation of an elegant protocol similar to
the creation of a work of art?